A new composite index for global soil plant atmosphere continuum drought monitoring combing remote-sensing based terrestrial water storage and vapor pressure deficit anomalies

•The remote sensing observed variables TWS and VPD are combined to develop a new index, named WDDI.•WDDI represents the composite water deficit of SPAC from the atmosphere to deep groundwater that is not only driven by climate but also driven by human activities.•Multiscalar drought events can be monitored well by WDDI by adjusting the weights between TWS and VPD.